﻿<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> 
<meta name="robots" content="all" /> 
<title>JS限制textarea输入框输入字数</title> 
<SCRIPT language="javascript"> 
<!-- 
function checktext(text) 
{ 
allValid = true; 
for (i = 0; i < text.length; i++) 
{ 
if (text.charAt(i) != " ") 
{ 
allValid = false; 
break; 
} 
} 
return allValid; 
} 

function gbcount(message,total,used,remain) 
{ 
var max; 
max = total.value; 
if (message.value.length > max) { 
message.value = message.value.substring(0,max); 
used.value = max; 
remain.value = 0; 
alert("留言不能超过 200 个字!"); 
} 
else { 
used.value = message.value.length; 
remain.value = max - used.value; 
} 
} 

--> 
</script> 
<style type="text/css"> 
<!-- 
* {padding:0; margin:0;} 
body, html {text-align:left; font-size:12px; line-height:150%; margin:0 auto; background:#fff; padding-top:20px;} 
fieldset {padding:10px; width:550px; margin:0 auto;} 
legend {font-size:14px; font-weight:bold;} 
.inputtext {border:none; background:#fff;} 
--> 
</style> 
</head> 
<body> 
<form action="SaveData.asp" method="post" onSubmit="return datacheck();"> 
<fieldset><legend>请输入内容</legend> 
<textarea name="Memo" rows="10" wrap=PHYSICAL cols="75" onKeyDown="gbcount(this.form.Memo,this.form.total,this.form.used,this.form.remain);" onKeyUp="gbcount(this.form.Memo,this.form.total,this.form.used,this.form.remain);"></textarea> 
<p>最多字数： 
<input disabled maxLength="4" name="total" size="3" value="200" class="inputtext"> 
已用字数： 
<input disabled maxLength="4" name="used" size="3" value="0" class="inputtext"> 
剩余字数： 
<input disabled maxLength="4" name="remain" size="3" value="200" class="inputtext"></td> 
</p> 
</fieldset> 
</form> 
</body> 
</html> 
